diff --git a/threads.c b/threads.c
--- a/threads.c
+++ b/threads.c
@@ -5,12 +5,9 @@
 
 #include <stdio.h>
 #include <stdlib.h>
-
 #include <pthread.h>
 #include <time.h>
 
-void *thread_func (void *vptr_args);
-
 void do_some_work (void)
 {
     time_t start_time = time (NULL);
@@ -18,6 +15,18 @@
     while (time (NULL) == start_time);  /* busy-wait for 0-1 seconds */
 }
 
+void *thread_func (void *vptr_args)
+{
+    int i;
+
+    for (i = 0; i < 20; ++i) {
+        fprintf (stderr, "  b\n");
+
+        do_some_work ();
+    }
+    return NULL;
+}
+
 int main (int argc, char **argv)
 {
     int i;
@@ -33,17 +42,6 @@
 
     pthread_join (thread, NULL);
 
-    exit (EXIT_SUCCESS);
+    return EXIT_SUCCESS;
 }
 
-void *thread_func (void *vptr_args)
-{
-    int i;
-
-    for (i = 0; i < 20; ++i) {
-        fprintf (stderr, "  b\n");
-
-        do_some_work ();
-    }
-    return NULL;
-}